KR20030012803A - Magnetic head - Google Patents

Abstract

PURPOSE: To efficiently suppress the temperature rising of a coil for generating a magnetic field in a magnetic head. CONSTITUTION: This magnetic head H is provided with a dielectric 3 having a surface 30 opposite a disk D with a space, and a magnetic field generation coil 2 provided inside or on the surface 30 of the dielectric 3. A heat conductive layer 4 having a heat conductivity higher than the dielectric 3 is provided to receive heat generated from the coil 2, and at least a partial surface of the heat conductive layer 4 is formed as a recessed and projected surface having a plurality of recesses and projections. Preferably, the recessed and projected surface is exposed from the surface 30 of the dielectric 3. More preferably, a plurality of recessed grooves constituting the recessed and projected surface are formed to be narrower from one longitudinal-direction end which becomes an air inlet toward the other longitudinal-direction end which becomes an air outlet.

Description

Magnetic head {MAGNETIC HEAD}

The present invention relates to a magnetic head used for recording and reproducing data on a magneto-optical disk or a magnetic disk. The term " magnetic head " in the present specification means a data recording and reproducing head having a magnetic field generating coil, and also includes a magneto-optical head. In the present specification, when simply referred to as "disk", both magneto-optical disks and magnetic disks are included.

When a current flows through the magnetic field generating coil of the magnetic head, the coil generates heat. When the amount of heat generated increases and the coil becomes overheated, the coil is thinned, and in extreme cases, a phenomenon called migration leading to disconnection may occur. In addition, when the temperature of the coil rises, the electrical resistance of the coil also increases, so that the power consumption required to generate a constant magnetic field also increases. Then, this increase in power consumption raises the heating temperature of the coil, resulting in an increase in the electrical resistance, and the above phenomenon accelerates. Therefore, conventionally, there is a means described in Japanese Patent Laid-Open No. 8-235556 as one means for improving such a problem.

As shown in FIG. 14, the means described in the above publication is such that the magnetic field generating coil 92 is attached to a slider 91 supported at the distal end of the suspension 90, and the disk D is formed on the outer surface of the slider 91. ), A plurality of line-shaped concave grooves 93 extending in the track direction (circumferential direction) of the disk D are formed.

According to such a structure, when the disk D is rotated and the slider 91 is made to float on the disk D, the air which flows at a high speed between this slider 91 and the disk D is concave in each of the slider 91. It passes through the groove 93. Therefore, the slider 91 can be cooled by contact with the said air, and the effect which suppresses the temperature rise of the coil 92 can be acquired.

However, in the said conventional means, there existed a case where it was not yet enough to suppress the temperature rise of the coil 92, as mentioned later.

In other words, the slider is generally made of a synthetic resin, but the synthetic resin is not very high in thermal conductivity. In addition, the coil for magnetic field generation is conventionally covered with a dielectric such as silicon oxide from the standpoint of insulation protection. Therefore, even if a part of the surface of the slider 91 is cooled by the high speed air flow, since the material with low thermal conductivity is interposed between this cooling part and the coil 92, the coil 92 itself does not cool sufficiently. In some cases, the heat dissipation efficiency was poor.

Further, the plurality of concave grooves 93 formed in the slider 91 are merely formed in the same width in each of the longitudinal directions. Therefore, the contact degree of the air which flows in each groove 93 with the surface which defines each recessed groove 93 is small, and there exists still room for improvement in improving the heat dissipation.

This invention is devised in view of such a situation, and makes it the subject to be able to suppress the temperature rise of the magnetic field generation coil of a magnetic head efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS The principal part sectional drawing which shows one Embodiment of this invention.

2 is an enlarged cross-sectional view of the main portion of FIG.

3 is a plan view of arrow III-III of FIG. 2;

Fig.4 (a)-(e) is principal part sectional drawing which shows an example of the manufacturing process of a heat exchanger layer.

5 is a plan view showing another embodiment of irregularities of the heat transfer layer.

6 is a plan view showing another embodiment of irregularities of the heat transfer layer.

Fig. 7 is a sectional view showing the principal parts of another embodiment of the present invention.

8 is a sectional view showing the principal parts of another embodiment of the present invention;

9 is a sectional view showing the principal parts of another embodiment of the present invention.

10 is a sectional view showing the principal parts of another embodiment of the present invention.

Fig. 11 is a sectional view showing the principal parts of another embodiment of the present invention.

FIG. 12 is a plan view showing an example of the surface form of a dielectric film of the magnetic head shown in FIG. 11; FIG.

13 is a plan view showing another example of the surface form of the dielectric film of the magnetic head shown in FIG. 11;

14 is an explanatory diagram of a prior art;

※ Explanation of code about main part of drawing ※

H: magnetic head

D: magneto-optical disk (disc)

2: coil

3: dielectric film (dielectric)

4: heat transfer layer

10: lens holder

11a, 11b: objective lens

30: surface (of dielectric film)

40: concave groove

In order to solve the said subject, this invention seeks the following technical means.

The magnetic head provided by the first aspect of the present invention is a magnetic head having a dielectric having a surface facing at a distance to a disk, and a coil for generating a magnetic field provided in or on the surface of the dielectric, A heat transfer layer having a higher thermal conductivity than the dielectric is provided to accommodate heat generated in the coil, and at least part of the heat transfer layer is formed as an uneven surface having a plurality of unevennesses.

According to this configuration, part of the heat generated in the coil is transferred to the heat transfer layer and then radiated to the outside through the heat transfer layer. Since the heat transfer layer has a higher thermal conductivity than the dielectric around the coil, much heat can be transferred from the coil to the heat transfer layer. Moreover, since the uneven part is formed in this heat transfer layer, the area of the heat transfer surface for heat dissipation can be taken large. Therefore, by doing this, the heat dissipation of the heat generated by the coil can be improved, and the temperature rise of the coil can be suppressed. As a result, it becomes possible to appropriately prevent the occurrence of vicious cycles such as the occurrence of movement due to overheating of the coil, the increase in power consumption due to the increase in electrical resistance, and the temperature rise of the coil.

In a preferred embodiment of the present invention, the uneven surface is exposed from the surface of the dielectric. According to this structure, part of the heat transfer layer can be brought into direct contact with the air flow generated between the surface of the dielectric and the disc as the disc rotates, whereby the heat dissipation of the heat transfer layer can be further improved.

The magnetic head provided by the second aspect of the present invention is a magnetic head having a dielectric having a surface facing at a distance to a disk and a coil for generating magnetic fields provided in or on the surface of the dielectric, A heat transfer layer having a higher thermal conductivity than the dielectric is located at a position opposite to the disc with the coil in the dielectric interposed therebetween, and a portion of the heat transfer layer is exposed from the surface of the dielectric.

According to this configuration, the heat generated in the magnetic field generating coil receives heat in a direction opposite to the disk in the heat transfer layer, and then the heat is discharged to the outside from the portion exposed to the outside from the dielectric surface in the heat transfer layer. Can be. The heat transfer layer has a higher thermal conductivity than the dielectric, and a portion of the heat transfer layer can be cooled by using an air flow generated by the rotation of the disk. As a result, in the above configuration, the same effect as cooling the magnetic field generating coil from the position opposite to the disk can be obtained. As a result, similarly to the magnetic head provided by the first aspect of the present invention, the temperature rise of the coil is appropriately suppressed and it is very suitable for preventing the occurrence of movement of the coil and the like.

The magnetic head provided by the third aspect of the present invention has a surface opposing the magnetic field generating coil and the disk at intervals, wherein the surface has a plurality of recesses for passing air when the disk is rotated. A groove is formed in the magnetic head, wherein each of the concave grooves becomes narrower toward the other end in the longitudinal direction, which becomes the outlet of the air, from the longitudinal one end, which becomes the inlet of the air, when the disk is rotated. It is characterized by being shaped. The surface on which the plurality of concave grooves are formed may be, for example, a surface of a dielectric provided to cover a coil for generating a magnetic field, or may be provided on the heat transfer layer of the magnetic head provided by the first and second aspects of the present invention. The surface of the corresponding part may be sufficient.

According to this configuration, when the air between the disk and the surface passes through each of the concave grooves as the disk rotates, the air is forced to contact the wall surface of the concave grooves. Therefore, it becomes possible to improve the cooling efficiency of the said surface compared with the case of the prior art which the width | variety of the each part of the longitudinal direction of several recessed grooves became the same. As a result, the temperature rise of the coil can be suppressed more than in the prior art, which is advantageous in preventing the occurrence of movement and the like.

A magnetic head provided by a fourth aspect of the present invention is a magnetic head having a surface facing a magnetic field generating coil and spaced apart from each other, wherein at least a portion of the surface includes a plurality of protrusions of the disk. It is formed as the uneven surface arrange | positioned distributed in a track direction and a tracking direction. Also in this case, as in the case of the magnetic head provided by the third aspect of the present invention described above, the surface formed as the uneven surface may be, for example, a surface of a dielectric provided to cover the coil for magnetic field generation. It may be a surface of a part corresponding to the heat transfer layer of the magnetic head provided by the first and second aspects of the present invention.

According to this structure, by forming a line groove extending in the track direction of the disk, the surface area of the uneven surface is increased and cooled by contact with air than in the case of the prior art in which the predetermined surface is uneven. It becomes easy to take large area of a column surface. In addition, when air flows between the disk and the uneven surface as the disk rotates, air is forced to all or substantially all of the plurality of protrusions, unlike when the air flows through the grooves in the line shape. By making it collide, it becomes possible to raise the grade which air contacts each part of the said uneven surface. Therefore, as with the magnetic heads provided by the first to third aspects of the present invention, it is preferable to improve the coil cooling efficiency and to prevent the occurrence of movement due to overheating of the coil.

Other features and advantages of the present invention will become more apparent from the following description of the embodiments of the invention.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described concretely, referring drawings.

1 to 3 show one embodiment of the present invention. As shown in FIG. 1, the magnetic head H of the present embodiment includes a lens holder 10, two objective lenses 11a and 11b held in the lens holder 10, and a magnetic field generating device. It is comprised as a magneto-optical head provided with the coil 2, the dielectric film 3 which covers this coil 2, and a pair of heat transfer layer 4. As shown in FIG.

The lens holder 10 is mounted on the carriage 50 and can be disposed below the magneto-optical disk D. This lens holder 10 is supported by the carriage 50 via support means (not shown) which are displaceable in the tracking direction (radial direction) of the magneto-optical disk D indicated by an arrow Tg, for example. Displacement in the direction is possible. The lens holder 10 can be displaced in the focus direction indicated by the arrow Fc by, for example, the driving force of the electromagnetic drive means 19. The magneto-optical disk D can be rotated at high speed about the imaginary line C of FIG. 1 by the drive force of a spindle motor (not shown). The recording layer 88 of the magneto-optical disk D is provided on the surface of the both sides of the magneto-optical disk D opposite to the lens holder 10 (see Fig. 2). Unlike the present embodiment, the recording layer 88 may be provided on the surface opposite to the surface of the magneto-optical disk D. However, this increases the distance between the recording layer 88 and the coil 2 and causes magnetic loss. At the same time, there is a fear that the laser light is affected by the distortion when the laser beam passes through the substrate of the magneto-optical disk D. Therefore, from a viewpoint of eliminating such a fault, it is preferable to set it as the structure similar to this embodiment. The surface of the recording layer 88 is covered with an insulating protective film 89 having light transparency.

The carriage 50 is movable in the tracking direction Tg by the driving force of a voice coil motor (not shown), for example. By the movement of the carriage 50, the seek operation which arrange | positions the lens holder 10 in the vicinity of the target track is performed. The laser beam is configured to travel toward the carriage 50 from the fixed optical unit including a laser diode (not shown), a collimator lens, or the like, and reach the start mirror 51 mounted on the carriage 50. . The laser light reflected upward by the start mirror 51 is focused by sequentially entering the objective lenses 11a and 11b, whereby a laser spot is formed on the recording layer 88. The fixed optical unit is also provided with a beam splitter or a photo detector. When the laser light is reflected by the recording layer 88, the reflected light is detected by the photo detector. Tracking control and focus control are possible by displacement of the lens holder 10 in a predetermined direction. However, for example, the tracking control can be performed by changing the inclination angle of the start mirror 51 and moving the reflection direction of the laser light in the tracking direction, and the details of these controls are not limited.

As well shown in Fig. 2, the magnetic field generating coil 2 is formed on a transparent substrate 60 such as a rectangle bonded to the objective lens 11b. For example, the substrate 60 is made of glass of the same material as that of the objective lens 11b, and is tightly spaced with respect to the objective lens 11b so as not to generate a gap in the interface between the objective lens 11b and the substrate 60. It is glued. In addition, in this invention, instead of forming the coil 2 on the board | substrate 60, the coil 2 is formed directly on the surface of the objective lens 11b, without using the board | substrate 60. It is also possible.

The coil 2 is formed by patterning a metal film such as copper into a predetermined shape, and can be manufactured by a semiconductor manufacturing process. The coil 2 is, for example, a two-layer structure having two conductive films 20a and 20b, and the two conductive films 20a and 20b are spiral coils having a spiral shape. . This coil 2 is provided so that the center axis L1 may be located on the extension line of the axis L2 of the objective lens 11b so as not to block the laser beam which has passed through the objective lens 11b. As shown in FIG. 3, a portion of each of the two conductor films 20a and 20b of the coil 2 is drawn out to the edge of the dielectric film 3 and the substrate 60, and the coil 2 Power supply terminal portions 20c and 20d are formed. As shown in FIG. 2, below the coil 2, a magnetic layer 61 having a thin film shape made of a permalloy or the like is provided. This magnetic layer 61 is for efficiently operating the magnetic field generated by the coil 2 in the direction of the magneto-optical disk D. As shown in FIG.

The dielectric film 3 is made of a dielectric material such as aluminum oxide or silicon oxide having a light transmissivity, and is formed on the substrate 60 so as to cover the magnetic layer 61 and the coil 2. The dielectric film 3 is formed by integrally stacking a plurality of thin film-like dielectric layers formed by forming the magnetic layer 61 or the thin film of the coil 2, and corresponds to an example of the dielectric in the present invention. The refractive index of the dielectric film 3 is preferably approximately equal to the refractive index of the substrate 60 or the objective lens 11b.

The pair of heat transfer layers 4 are made of a metal such as copper, which has a higher thermal conductivity than the dielectric film 3. In the present embodiment, the pair of heat transfer layers 4 have a heat dissipation function for suppressing the temperature rise of the coil 2 as described later, and at the same time based on the electrostatic capacity, the magneto-optical disk D And serve as a conductor or a sensor for determining the distance between the magnetic head and the magnetic head H. In other words, as the distance between the pair of heat transfer layers 4 and the recording layer 88 becomes smaller, the capacitance between them becomes larger. Therefore, the distance between the magneto-optical disk D and the magnetic head H can be obtained based on the value of the capacitance, and the pair of heat transfer layers 4 help to detect the capacitance. The interval data between the magneto-optical disk D and the magnetic head H1 obtained based on the electrostatic capacitance is used to, for example, increase the accuracy of focus control.

The pair of heat transfer layers 4 are exposed from the surface 30 of the dielectric film 3 so that the pair of heat transfer layers 4 can face the magneto-optical disks D through a small gap. As shown in FIG. 3, the pair of heat transfer layers 4 exclude the portion of the dielectric film 3 surface 30 that overlaps with the formation region of the coil 2 so as to exclude the dielectric film 3. ) Is formed over a large area of the surface 30. However, the pair of heat transfer layers 4 are divided into two through a gap of a suitable width s extending in the radial direction of the coil 2. This adopts a magnetic field modulation method as a data recording method for the magneto-optical disk D, and makes it difficult for the dielectric current to flow in the heat transfer layer 4 when the high frequency current flows in the coil 2, thereby making the coil 2 This is to prevent the magnetic field generated by) from being weakened by the magnetic field generated based on the dielectric current.

The surface facing the magneto-optical disk D of each heat-transfer layer 4 has an uneven surface having a plurality of grooves 40 and a plurality of protrusions 41 positioned between the plurality of grooves 40. It is formed as. Each groove 40 extends in the track direction indicated by the arrow Tc of the magneto-optical disk D. As shown in FIG. However, the width | variety of each groove | channel 40 is not uniform at each place, and if the rotation direction of the magneto-optical disk D is a direction of arrow N1 of FIG. 3, for example, the longitudinal direction one end part 42a of the upstream side The width Sb of the other end 42b in the longitudinal direction on the downstream side is smaller than the width Sa of. More specifically, the pair of wall surfaces 43a and 43a defining the width of each groove 40 are directed toward the other end 42b from one end 42a of each groove 40 to each groove 40. It is a non-parallel surface which gradually decreases the width of.

Each heat transfer layer 4 can be manufactured by a semiconductor manufacturing process similarly to the coil 2 or the magnetic body layer 61. As an example thereof, first, as shown in Fig. 4A, a copper base layer 49a is formed on the dielectric film 3a (part of the dielectric film 3) serving as a base by sputtering or vapor deposition. . Subsequently, as shown in FIG. 4B, after the first resist 69a is applied on the base layer 49a to perform exposure and development treatment, the first resist 69a is formed on the surface of the base layer 49a. The copper layer 49b is further formed by growing copper by plating or the like at the portion not covered by the?). Thereafter, as shown in FIG. 4C, after patterning the second resist 69b on the surfaces of the first resist 69a and the copper layer 49b, a plurality of copper layers 49b are formed. A copper layer 49c having a line shape is formed. After finishing this process, as shown in FIG.4 (d), the 1st and 2nd resists 69a and 69b are removed, and after that, the base layer 49a is performed by ion milling, for example. Remove unnecessary parts of the Then, as shown in Fig. 4E, the heat transfer layer 4 can be formed. Such a series of processes can be performed in parallel with the manufacturing process of the coil 2, or following the manufacturing process of the coil 2 efficiently.

Next, the operation of the magnetic head H will be described.

When data recording to the magneto-optical disk D is performed by the magnetic field modulation method, the recording layer 88 is irradiated by continuously irradiating a laser beam onto a desired track of the recording layer 88 while rotating the magneto-optical disk D. The predetermined magnetic substance of is raised to the Curie temperature. On the other hand, the high frequency current flows through the coil 2, and the magnetic flux direction of a magnetic field is changed. This controls the magnetization direction of the magnetic body constituting the recording layer 88. In this data recording process, a part of the heat generated from the coil 2 is transferred to the pair of heat transfer layers 4 through the dielectric film 3 and is external (air) through the pair of heat transfer layers 4. Medium). Each heat transfer layer 4 is excellent in thermal conductivity, and since the surface thereof is a concave-convex surface with a large heat transfer area exposed to the outside of the dielectric film 3, excellent heat dissipation effect can be obtained.

In addition, between each heat transfer layer 4 and the magneto-optical disk D, a high-speed air flow is generated by the rotation of the magneto-optical disk D, and the surface of each heat-transfer layer 4 is connected to this high-speed air flow. Exposed. Therefore, the heat transfer layer 4 is actively cooled by this high speed air flow. As shown by arrow N2 of FIG. 3, the high velocity air flow enters into each groove 40 from one end 42a and faces the other end 42b. On the other hand, as mentioned above, the width | variety becomes narrower in each groove | channel 40 as the other end part 42b becomes. Accordingly, the degree of contact of the high speed air stream with the pair of wall surfaces 43a of the grooves 40 can be increased to further promote the cooling of the heat transfer layer 4 by the high speed air stream.

In this way, when the heat dissipation is efficiently performed in the heat transfer layer 4, the temperature rise of the coil 2 can be suppressed by this. Thereby, the movement of the coil 2 can be prevented. In addition, the increase in the electrical resistance of the coil 2 due to the temperature rise can be prevented, so that a chain phenomenon such as an increase in the power consumption and an increase in the heat generation temperature of the coil due to the increase in the power consumption can be suitably suppressed. It becomes possible. In this embodiment, the heat transfer layer 4 serving as a conductor or a sensor for determining the distance between the recording layer 88 of the magneto-optical disk D and the magnetic head H based on the electrostatic capacitance is used. It is comprised so that the cooling effect of the coil 2 may be improved. Therefore, the structure is rational, and it is also possible to reduce the number of components of the magnetic head H, and to suppress the increase in manufacturing cost as much as it can simplify its construction.

5 to 13 show another embodiment of a magnetic head according to the present invention. In these drawings, the same or similar elements as in the above embodiment are given the same reference numerals as in the above embodiment.

In the configuration shown in FIG. 5, a plurality of protrusions 44 having a rectangular shape or the like is a means for making the surface of each heat transfer layer 4 exposed from the dielectric film 3 covering the coil 2 into an uneven shape. Are distributed in each of the tracking direction Tg and the track direction Tc.

According to such a structure, since the some protrusion part 44 is disperse arrange | positioned, since the area of the surface used as the heat-transfer surface of each heat-transfer layer 4 can be enlarged, the outstanding cooling effect can also be obtained. In addition, when the high-speed airflow is generated between the magneto-optical disk and the surface of each heat-transfer layer 4 by rotating the magneto-optical disk, as shown by arrow n1, the high-speed airflow is applied to each of the protrusions 44. Can collide with the sides. Therefore, the cooling efficiency can be improved also by such an effect, and it becomes very suitable to suppress the temperature rise of the coil 2.

In the structure shown in FIG. 6, the some groove 45 of each heat-transfer layer 4 is formed as what is called a parallel groove prescribed | regulated by the wall surface 45a parallel to each other.

According to this configuration, when the high speed air flow generated between each heat transfer layer 4 and the magneto-optical disk enters each groove 45 as indicated by arrow N3, the high speed air flow is generated in each heat transfer layer 4. The degree of contact with the surface is lower than that of the configuration shown in FIG. 3 or 5. However, as compared with the case where the surface of each heat-transfer layer 4 becomes planar shape which does not have an unevenness | corrugation, it is possible to improve the cooling efficiency of each heat-transfer layer 4, and this invention provides each heat-transfer layer 4 As a means for roughening the surface of the structure, a structure as shown in FIG. 6 may be employed.

In the structure shown in FIG. 7, the heat transfer layer 4A having a higher thermal conductivity than the dielectric film 3 is provided in the portion of the dielectric film 3 near the substrate 60 than the coil 2. This heat transfer layer 4A performs the same role as the magnetic body layer 61 of the above-mentioned embodiment, and consists of a magnetic body. The heat-transfer layer 4A is formed over a relatively wide area of one side of the substrate 60, and at least one surface of both surfaces of the heat-transfer layer 4A is provided with a plurality of protrusions 48a and recesses 48b. It has the uneven surface which has.

According to such a structure, since one surface of 4 A of heat-transfer layers is an uneven surface, since the surface area of this heat-transfer layer 4A becomes large, the heat dissipation of this heat-transfer layer 4A can be improved by that much. The heat transfer layer 4A is entirely or substantially entirely embedded in the dielectric film 3, but since the heat transfer layer 4A has a higher thermal conductivity than the dielectric film 3, the heat generated from the coil 2 is reduced. It can diverge through the heat transfer layer 4A. Therefore, also in this embodiment, the effect which suppresses the temperature rise of the coil 2 can be acquired.

As understood from the embodiment shown in FIG. 7, in the present invention, the portion (heat transfer layer) used for dissipating heat does not necessarily have to be exposed to the surface of the dielectric film 3. Therefore, for example, the uneven surface of the heat-transfer layer 4 of the embodiment shown to FIG. 1 thru | or 3 may be comprised by the dielectric film 3, and when such a structure is employ | adopted, It is included in the technical scope.

In the structure shown in FIG. 8, the heat-transfer layer 4B has the structure by which the 2nd layer 46b was laminated | stacked on the 1st layer 46a provided in the position near the board | substrate 60 rather than the coil 2. As shown in FIG. Both of these first and second layers 46a and 46b have higher thermal conductivity than the dielectric film 3, and the second layer 46b has a surface that is exposed from the surface 30 of the dielectric film 3 and is magneto-optical. It is formed so as to oppose the disk D. The first layer 46a plays the same role as the magnetic layer 61 shown in FIG. 2 and is made of magnetic material.

According to such a structure, the heat toward the board | substrate 60 among the heat | fever which generate | occur | produced from the coil 2 is efficiently transmitted to the heat transfer layer 4B. This heat is efficiently released to the outside from the surface facing the magneto-optical disk D of the heat transfer layer 4B. According to the present embodiment, heat that is intended to remain inside the thickness direction of the dielectric film 3 can be actively induced and released on the surface side of the dielectric film 3. Therefore, the temperature rise suppression effect of the coil 2 becomes excellent.

In the configuration shown in FIG. 9, the heat-transfer layer 4C is a first layer 47a (magnetic material layer) located closer to the substrate 60 than the coil 2, and an agent on which the surface is exposed from the dielectric film 3. It consists of the 2nd layer 47b and the intermediate | middle layer 47c which connects these 1st and 2nd layers 47a and 47b.

According to such a structure, it becomes easy to make the area of the 2nd layer 47b larger than the area of the 1st layer 47a, and to enlarge the area of the surface by which the heat-transfer layer 4C is exposed from the dielectric film 3 surface. . Therefore, it becomes more preferable to raise a heat radiating effect.

In the structure shown in FIG. 10, the upper surface (exposed surface) of the 2nd layer 47b of the heat-transfer layer 4D is formed as an uneven surface which has some unevenness | corrugation.

According to such a structure, the heat dissipation property can be improved more as much as the surface area of the surface which contacts the air of the heat-transfer layer 4D can be enlarged. When the exposed surface unevenness | corrugation of the heat-transfer layer 4D is made into the same form as shown in FIG. 3, FIG. 5, or FIG. 6, the same effect as what was demonstrated with reference to those drawings can be expected.

In the structure shown in FIG. 11, the substantially whole area | region except the part which laser beam permeate | transmits in the surface 30 of the dielectric film 3 is formed as an uneven surface. This uneven surface has the same shape as that of the uneven surface of the heat transfer layer 4 shown in FIG. 3 or 5. Specifically, the uneven surface of the dielectric film 3 has a plurality of grooves 39 and a plurality of protrusions 38, as shown in FIG. 12, so long as each groove 39 is defined. The width | variety of the pair of wall surfaces 39a becomes a non-parallel surface which becomes narrow gradually as it goes downstream with respect to the direction (arrow N5 direction) of a high speed air flow. Alternatively, the uneven surface of the dielectric film 3 has a configuration in which a plurality of protrusions 37 having a rectangular shape or the like are distributed in the tracking direction and the track direction as shown in FIG. 13.

According to such a structure, the area of the surface 30 used as the heat transfer surface of the dielectric film 3 can be enlarged, and the heat transfer described with reference to FIG. 3 or 5 on the surface 30 of the dielectric film 3. By the same principle as in the case of the uneven surface of the layer 4, the high-speed air flow generated between the surface 30 of the dielectric film 3 and the magneto-optical disk D acts efficiently. Therefore, the heat dissipation at the surface portion of the dielectric film 3 can be improved as compared with the surface of the dielectric film having a simple planar shape or only a plurality of simple parallel grooves formed on the surface of the dielectric film. Therefore, it becomes preferable to suppress the temperature rise of the coil 2.

The content of this invention is not limited to embodiment mentioned above. Specific configuration of each part of the magnetic head according to the present invention can be variously changed design.

For example, the dielectric in the present invention is not limited to the dielectric film formed on the substrate surface. In the present invention, for example, a coil can be formed directly on the surface of the objective lens, and the objective lens can also be used as the dielectric in the present invention.

The magnetic head according to the present invention includes a slider which floats with a small distance from the disk, and may be configured as a magnetic head of a type in which a coil is provided on the slider. Moreover, the magnetic head which concerns on this invention can also be comprised as a magnetic head which does not have an objective lens. When a coil is formed into a thin film by a semiconductor manufacturing process, its manufacture is easy, but it is not limited to this again.

As can be seen from the above description, according to the magnetic head according to the present invention, it is very suitable for effectively suppressing the increase in the heat generation temperature of the magnetic field generating coil and preventing the movement of the coil or the increase of the power consumption. .

Claims (5)

A magnetic head having a dielectric having a surface opposed to a disk at a distance, and a coil for generating a magnetic field provided on or in the dielectric. A heat transfer layer having a higher thermal conductivity than the dielectric is provided to receive heat generated from the coil, At least one surface of the heat transfer layer is formed as an uneven surface having a plurality of unevenness. The method of claim 1, The uneven surface is exposed from the surface of the dielectric. A magnetic head having a dielectric having a surface opposed to a disk at a distance, and a coil for generating a magnetic field provided on or in the dielectric. In the dielectric, a heat transfer layer having a higher thermal conductivity than the dielectric is located at a position opposite to the disk with the coil interposed therebetween. A portion of the heat transfer layer is exposed from the surface of the dielectric. The magnetic field generating coils and disks face each other at intervals. A magnetic head having a plurality of concave grooves provided on the surface to allow air to pass through when the disk is rotated, Each of the concave grooves has a shape in which the width becomes narrower as it goes toward the other end in the longitudinal direction, which becomes the outlet of the air, from the one end in the longitudinal direction, which becomes the inlet of the air, when the disk rotates. head. A magnetic head having a surface facing at a distance to a magnetic field generating coil and a disk, At least a portion of the surface is a magnetic head, characterized in that a plurality of protrusions are formed as uneven surfaces in which the plurality of protrusions are distributed in the track direction and the tracking direction of the disk.